Cagnazzo

Cagnazzo is the water fiend and hence is weak to Thunder and Ice spells. It's how you use them here that will make your battle harder or not. Cagnazzo goes into various modes, like Turtle Mode (where he'll heal himself) and Water Mode (where a pool of water will gather around him, allowing him to cast Tsunami). When he's in these modes, have Tellah use Thundaga or Blizzaga on him to not only do 1,000+ HP of damage to him, but to break him out of whatever mode he's in. Using Thundaga or Blizzaga otherwise will only do about half of the damage. It's at these times that Tellah and Palom should be defending, Porom should be healing the party, and Cecil and Yang should do physical attacks. In only a few rounds, this foe will be destroyed.